Process of and apparatus for treating materials



June 23, 1936. w. A. DARRAH PROCESS OF AND APPARATUS FOR TREATINGMATERIALS Filed. June 20, 1930- m l I I MMMMIJ l fa I Ii 4 #3 22 0%- 5 A-23 i 14 l Fiyarel Inven for Patented June 23, v 1936 UNITED STATESPROCESS OF AND APPARATUS FOR TREATING MATERIALS William A. Darrah,Chicago, Ill.

Application June 20, 1930, Serial No. 462,522

12 Claims.

This invention relates to processes of treating materials to causecertain changes in either their physical or chemical properties. Theprocess may be broadly described as a method of heat application,although it is carried out by electrical means. Most of the changes tobe carried out by this equipment will fall in the class of chemicalchanges, but the process and equipment should not be limited to chemicalreactions only.

Some of the objects of my invention are to provide simple, durable,economical means and a controllable and eflicient process for carryingout reactions which are now only handled with difficulty.

Many types of reaction may be carried out with my process and equipment,depending of course on the method of operation and the materials used. Atypical example of the method of using my process and equipment is inconnection with those reactions which take place between water or watervapor and various compounds of hydrogen and carbon.

The fie'lds of these reactions are so extensive that I do not wish to berestricted to any particular group and the description here given shouldbe interpreted in its broadest terms, although for purposes of clearnessspecific reference will be made from time to time to certain definitematerials.

The figure shows diagrammatically and partly in section one form of mydevice.

Referring to the drawing I indicates a storage tank or source of supplyfor materials to be treated. 2 indicates a reaction chamber or containerwithin which the reaction takes place. 3 indicates a separatingcontainer through which the material from container I passes, during theprogress of reaction. Container 2 is provided with heating means showndiagrammatically as a resistance coil 4 and insulation or supportingmaterial 5 surrounds the chamber 2. In order to still further controlthe temperature within chamber 2 a coil or other device 5 is provided.This may be used to circulate cooling fluids, as for example cold waterin certain cases or it may be employed to supply heat by passing steamor heating fluids either in place of resistance coil 4 or supplementingthis coil. An automatic control device (not shown) may be provided toregulate the flow of material through coil 5, thus maintaining anydesired temperature within chamber 2.

The material to be treated on leaving container I passes through duct 1and is controlled by valve member 8 which if desired, may be operated byfloat member 9 through lever system I0. Float 9 therefore serves toautomatically hold the level of the liquid in container 3 at apre-determined value which may be adjusted by moving float 9 relativelyto lever system ID by means of adjusting nut II. An electrode I2 isdisposed in chamber 3 in any desired manner and serves primarily to makecontact between the material in chamber 3 and the electric circuit.Another electrode I3 disposed in chamber 2 serves to complete theelectric circuit. It will be noted that the current in passing throughmy device travels through container 3 leaving by the opening I4 showndiagrammatically in its lower portion and then through the liquid incontainer 2 to electrode I3. It should be understood that the currentmay flow in either direction or alternating current may be employed.

Control rod I5 adjustably supported in top I6 of container 3 serves bybeing raised or lowered to restrict opening I4 for purpose later to bedescribed. The position of rod I5 shown in solid illustrates a positionin which opening I4 is considerably restricted, whereas the dotted lineabove member I5 indicates the upwardtravel when opening I 4 is wellopened. Adjustable nut member I! illustrates a diagrammatic means ofadjusting and holding member I5 in place. It is desirable that, at leastthe lower end of member I5 be of insulating material and I find itconvenient to construct the entire lower portion of member l5 of quartzor similar substance. In the same way I find it convenient to constructa portion of container 3 from quartz or other very durable insulatingmaterial capable of withstanding high temperatures and thermal shock.The portion of container 3 surrounding opening I4 should be made of amaterial having these properties. The remainder of container 3 may beconstructed of any desired insulating material.

The level of liquid in container 2 may be automatically controlled bymeans of float member I8 which is adjustably supported to lever I9bymeans of adjusting nut 20. The movement of float member I8 serves toactuate valve 2| in discharge duct 22 thereby controlling the rate offlow from container 2. 23 indicates a reservoir or storing means for thefinished product after passing through my equipment.

A thermostat 24 may be provided to hold the temperature within container2 at any pre-determined value by means of varying the current passingthrough resistance coil 4. A hand operated rheostat 25 provides furtheradjustment for the temperature within container 2. 26 indicates a motorand 21 a generator which is shown diagrammatically as a source ofalternating current, although direct current may be used with myequipment and in some cases is a definite advantage as will be laterdescribed. In order to make clear one circuit for my equipment Iindicate a transformer 28 supplied by generator 21 and show a variabletap 29 on the secondary of transformer 28, thus making it possible toobtain varying voltages between electrodes I 2 and I3. A rheostat 30 isalso provided to control the current flowing between electrodes l2 andI3 and in certain cases, as for example the use of relatively highfrequencies, I provide a condenser 3| which I have found in practicegives a material difl'erence in the operation of this equipment in manycases.

It will be evident that by varying the speed of motor 26 and, therefore,generator 2'! I can obtain various frequencies in the alternatingcurrent circuit which also gives me an additional means of controllingthe reactions which take place in this equipment.

It should be understood that by varying the level of the liquid incontainer 3 and the level of the liquid in container 2 I can vary (orautomatically hold constant) the pressure at the reaction point, whichis adjacent, or within outlet I 4.

I therefore provide means for controlling the pressure and temperatureof the liquid at the point of reaction and by passing a current of theproper density I am able to cause an intense local heating at, oradjacent to outlet 14. When the outlet I4 is kept rather small so thatthe current density is high an interrupted arc occurs in and adjacent tooutlet l4. The interruptions of the arc appear to be ordinarily muchhigher in frequency than the ordinary source of current supplied,although the frequency depends very greatly upon the pressure andtemperature of the liquid, the composition of the liquid, currentdensity, voltage and other factors.

One function of variable condenser 3| is to control in a measure thefrequency with which interrupted arc occurs at or adjacent to outlet l4.

It will also be apparent that the rate of travel of the liquid tobetreated from container I into container 2 through outlet It willdetermine the time that the liquid is exposed to the arc and, therefore,one of the important factors in connection with the reaction.

As an illustration of one application of my invention I may cite thetreatment of an emulsion of a hydrocarbon such as kerosene or fuel oilwith water. An emulsion may be prepared in any of the well known methodsas for example by the use of a soluble soap, by means of bentonite addedto water and agitated with the hydrocarbon, by means of sodium silicateand many others. I prefer to have a homogeneous uniform emulsion andpreferably one which will stand a fairly high temperature range withoutbreaking down. I may add to the emulsion certain materials which appearto act as catalytic agents such as vanadium oxide, ferric chloride,manganese chloride, cobalt chloride, etc. I do not wish to be restrictedto any particular catalytic agent as obviously certain materials aremore effective with some classes of compounds than others. I do notclaim to have invented the use of a catalytic agent but do consider theaddition of a catalytic material in the practice of the material issubjected in my process.

my invention to represent a portion of my invention.

In practice I prefer to have the emulsion as liquid as possible from thestandpoint of ready handling, but on the other hand the ratio of waterto hydrocarbon should be maintained ap proximately in proportion to therelative quantities taking place in the chemical action. In general itwill be found advisable to use a considerable excess of water or othersolvent. The excessive amount of water is an objection in that itrepresents a diluting material which must be handled and which must beheated and cooled. It, therefore, represents a loss of heat over thetheoretical operating conditions.

It is, of course, well known that certain oxidations occur when water orwater vapor is heated under pressure as for example in an autoclave.Many reactions of this class are now carried on commercially and theyinvolve considerable difiiculty and expense. The available pressures bythe auto-clave method are limited particularly at high temperatures.Obviously known materials will not stand simultaneously hightemperatures, as for example 1000 to 2000 and high pressures as forexample 1000 pounds per square inch under practical working conditions.It is, therefore, necessary to use many round-about methods to obtaincommercial re- ,sults with auto-claves and similar equipment.

A further difliculty with the auto-clave method of heating is theinability to apply the heat economically at the desired point.

My invention, therefore, serves to provide a means for accomplishingreactions of the class now carried on in auto-claves where variousmaterials are heated together at relatively high temperatures andpressures. My process and equipment, however, give only local hightemperatures and local high pressures, thus making it possible toprovide equipment which will have a long life and high efliciencywithout incurring a great expense.

While the temperature of the liquid in container 2 as indicated bythermostat 24 may only range from to 200, it is readily possible toobtain a temperature range from 1000 to 2000 in or adjacent to outlet14. Since all of the emulsion or other material being treated passesthrough outlet I4 all of the material passing through my equipment willbe successively subject to very high temperatures. The current densitythrough outlet I4 is one of the essential factors in controlling thetemperature to which Another factor is the rate of flow of the materialthrough outlet l4.

It is therefore apparent that while the major portion of the equipmentwith which I am provided is subjected to only very moderate temperaturesthe material being treated may be subjected to very high temperatures.

Regarding the other factor of pressure which is of course more or lessdefinitely connected with temperature, it will be evident that apressure gauge if placed in the liquid of container 2, adjacent tooutlet It might show only a very moderate pressure, as for example thatresultant from the height of the liquid above outlet M. In actualpractice this head may range from one foot to many feet, depending onthe materials treated and the desired product. On the other hand, inpassing through outlet H the liquid from container 3 is subjected toextremely high temperatures as previously discussed, which in turn formsinstantaneous portions of vapor at very high pressures rangingordinarily many pounds or even hundreds of pounds per square inch. Thispressure is, of course, not maintained continuously except in the outletl4 and in constructing my device I prefer to make the length of outlet Il quite appreciable as illustrated diagrammatically in the drawing.Momentarily, therefore, portions of the material being treated aresimultaneously subjected to very high tem-- peratures and pressures. Onefactor which controls the maximum temperature to which the vapors aresubject is the high lag of the liquid material in moving away from thesmall highly heated bubbles caused by the current. In other Words, whendealing with relatively high frequencies in connection with theformation of the arcs and therefore the bubbles and portions ofmaterials heated to high temperatures the liquid behaves in the mannerof a very viscous solid. This makes it possible, therefore, formomentary pressures of extremely large amounts to occur.

The temperature of the liquid in and adjacent to outlet I l appearstocontrol the size and speed with which the bubbles of vapor are produced.As a theory for explaining this action, I am of the opinion that whenthe liquid in and adjacent to outlet I4 is close to the boiling point itflashes into vapor very readily and is slower to condense. On the otherhand if the liquid in container 2 and in and adjacent to outlet I4 isrelatively far below its vapor point a greater interval results before agiven amount of electrical energy can convert the liquid into vapor.Bubbles of vapor are, therefore, slower in forming under theseconditions and somewhat quicker in condensing. In general I obtain themost satisfactory results in forming oxidation products of hydrocarbonsby using a relatively low temperature, as for example 40 or 50 F. incontainers 2 and 3. Where, however, the materials to be treated reactwith considerable ease and require relatively low temperatures andpressures, I am able to get a greater volume of product treated at ahigher efliciency by carrying a relatively high temperature incontainers 2 and 3, as for example 150 to 200 F.

Obviously these are points which vary with the materials treated and thedesired product to be produced and I do not wish to be restricted to anyset of conditions in the process of my invention.

While I have previously referred to the reactions taking place betweenhydrocarbons and water vapor it will be apparent that I may treat anyliquids or liquid emulsions in this manner. In place of water I may usewater solutions of various materials or such liquids as sulphuric acid,acetic acid, carbon tetrachloride, alcohol, etc. I may also use a widerange of materials in place of the hydrocarbon and I do not wish to berestricted to any particular series of hydrocarbons as the variousso-called aromatic series, parafiin series, etc., are equally applicableto my process.

While my process is well adapted to the formation of oxidation oraddition compounds, it may also be used in the proportion ofchlorinated, sulphonated and other hydrocarbons.

It will be apparent that my process consists largely of a thermal andpressure treatment, although in certain cases particularly where directcurrent is used there appears to be an additional effect due possibly tothe electrolytic decomposiparafiin, asphalt, etc.

tion of the solution. In most cases this is materially less importantthan the pressure and thermal effects.

I have found that a wide range of materials or emulsions may be treatedby my process. When applying a low voltage with a relatively largecurrent, it is desirable to have the conductivity of the liquid treatedrelatively good, as otherwise too great an amount of heating will occurin containers 2 and 3 and not enough heating in outlet M. It ispossible, however, to produce decided results with my invention whenusing materials whose insulating value corresponds to that of oil havingsmall amounts of water dissolved in it or mixture of distilled water oremulsions such as In cases of this kind it is necessary, of course, toapply higher voltages between terminals I2 and I3, to use smaller totalcurrents and therefore a materially smaller opening in outlet M. It willbe apparent from a consideration of these factors that it is impracticalI to confine this invention to any specific set of currents, voltages orfrequencies as these must be adjusted in each case to conform to thematerials being treated and the products desired.

In certain cases some of the materials resulting from the heat treatmentin this process become either gases or vapors which must be treated assuch. In order to take care of this condition I may provide an outletduct 3| connecting to a with cooling fins 33. Condenser 32 connects topipes 34 and 35. 35 shows diagrammatically a means of deliveringcondensed liquids to storage container 36, while pipe or duct 35 showsmeans of conducting the permanent gases to storage container 31. Valvemembers 38 and 39 control the flow of material from the condenser to thestorage for gas or liquid respectively. It will be noted that pipemembers 34 and 35 together with the associated equipment serve as aseparating device for removing liquids from gases or vapors andconducting each to their desired storage point.

This invention does not include any specific form of condenser, gasseparator or storage vessels. It should be understood, therefore, thatany practical equipment for this purpose may be substituted withoutdeparting from the scope of my invention.

It should also be understood that in referring to emulsions or mixturesI do not exclude the use of solutions as there are many instances inwhich sufiicient water may be dissolved in the material being treated tosustain the necessary reaction.

During the operation of my equipment I have noted as specified above,that a series of small arcs or high temperature zones, which frequentlygive off light as well as heat, are produced in outlet l4 and adjacentthereto. It appears that these arcs arecaused partly by an interruptionof the current flow due to the formation of a series of small bubbles orspacers, which become relatively poor insulators and which serve tointerrupt the flow of liquid from container 3 through butlet I4.

There appear to be a certain set of voltage and current conditions whichgive the most eifective treatment. It is obviously desired to subjectall of the liquid to the same treatment. A long interval between heatingperiods (arcs) usually results in a definite amount of material passingthrough outlet l4 without being subjected to the pressure andtemperature conditions. I. have found that the amount of material thusescaping condenser 32, which is shown diagrammaticallytreatment or theamount'of material being subjected to a diminished treatment isordinarily reduced when the frequency of the current supplied isincreased the frequency of the production of arcs is increased. Ingeneral an increase in the applied voltage and the volume of currentwill also produce a more uniform product. There are limits, however, tothis statement as when using extremely high voltages with too large anopening in outlet l4 proper treating conditions are not obtained. Ingeneral it may be stated that the desired results are obtained when theheat produced by the current passing through outlet I4 is sufiicient tosupply the necessary heat units to raise the liquid to the desiredtemperature within the desired time.

It should be understood therefore that one phase of my inventionincludes a definite control of the temperature and pressure to which theliquid is subjected and simultaneously controlling the time interval,and rate of flow.

Certain materials and certain reactions require closer control thanothers. The exact condition depends so largely on the nature of thematerials being treated that it is impractical to specify a given set ofconditions. In general it may be stated that the higher hydrocarbons, asfor example, paraflin or related materials will permit a greater rangeof temperature and pressure conditions than will the simplerhydrocarbons such as ethylene, etc. The following equations illustratetypes of reactions which may take place in carrying out my invention.

It should be understood, however, that while I have shown in theseequations only reactions between hydrocarbons and water that thereactions may take place between any group of chemical compounds.

Having now fully described my invention what I claim as new and wish tosecure by Letters Patent in the United States is as follows:

1. The process of oxidizing hydrocarbons in an electrolyticallyconductive aqueous emulsion, by subjecting consecutive portions of saidliquid successively to instantaneously controlled high temperature andhigh pressure, resulting from an electric are immersed in said liquid.

2. The process of treating materials containing a hydrocarbon suspendedin an electrolytically conductive aqueous solution, by subjectingportions of the liquid to instantaneous high temperatures and pressuresfor a controlled time interval, by passing an electric current throughsaid liquid while in a confined space, said current density beingsufficient to create a localized arc within said restricted passagewayhaving said conducting liquid at the ends of said passageway for areterminals.

3. The process of partially oxidizing hydrocarbons while suspended in anelectrolyte which consists in passing said liquid at a controlled rateconsecutively through a restricted passage, causing an alternatingelectric current of relatively high density to produce an arc in saidliquid material in a coherent liquid phase, while in'said passage,thereby strongly heating said liquid and having a portion of saidelectrically conducting liquid for terminals and finally removing saidtreated material at a controlled rate, thus determining the productformed.

4. An apparatus for treating hydrocarbons suspended in an electrolyte,consisting of a treating duct of relatively long length and smallsection with an enlargement near each end, means for maintaining aconstant normal pressure head on the material in said treating duct,means for 5 producing a controlled temperature in said treating duct,said means comprising two electrodes immersed in'said conducting liquidlocated in said enlargements adjacent the ends of said treating duct andmeans for removing said mal terial after treatment, said electrodesbeing arranged tocreate an electric arc in said treating duct.

5. An apparatus for treating hydrocarbons suspended in an electrolyteconsisting of a treating l duct formed from insulating material, meansfor maintaining a constant normal pressure head on the material in saidtreating duct, electrical means for heating said liquid to a controlledtemperature while in said treating duct, said means comprising twoelectrodes located adjacent the terminals of said treatingrduct andconnected to a source of electric potentials and means for removing saidmaterial after treatment, said treating duct and electrodes beingarranged so as to create an are within said treating duct.

6. An equipment for treating materials suspended in an electrolyte,comprising a treating duct of electrically insulating materials, meansfor maintaining a normal pressure head on the material in said duct,means for controlling the rate of flow of said material through saidtreating duct and means for producing high temperatures and pressures insaid treating duct comprising a pair of electrodes immersed in saidliquid, one of said electrodes being located adjacent to each end ofsaid treating ducts, said electrodes serving to cause an arc in saidtreating duct.

'7. The process of heat treating materials con- 40 taining carboncompounds and an electrolyte, which consists in passing said materialsthrough a treating duct at a controlled rate, maintaining a controllednormal pressure on said materials in said treating duct momentarily andsubjecting successive portions of said material while in the liquidphase and in said treating duct to the direct flow therethrough of anelectrical current of high density, thus causing an electric arc withinsaid liquid and thereby strongly heating said liquid, said treating ductbeing subjected to an intermittent arc.

8. An equipment for heat treating an aqueous mixture of hydrocarbons andelectrolyte, consisting of a, treating duct of electrically insulatingsite ends of said restricted passage thus electrically heating saidmaterial while in said passage by means of an electric are formed bysaid electrodes and variable means for controlling the effective crosssection of said passage between said electrodes, thus varying thecurrent density in said passage and thereby controlling the productformed by said treatment.

10. In a device for electrically heat treating material containing ahydrocarbon suspended in an electrolyte, a treating duct, variable meansfor restricting the cross section of said treating duct, thereby causinglocalized arc heating, said arc being located within the restrictedsection of said duct having the liquid at the ends of the duct asterminals for said arc, a reservoir supplying said material to saidtreating duct, electrodes adjacent the ends of said duct, and means forcontrolling the rate of flow of material through said treating duct.

11. The process of heat treating materials containing a hydrocarbonsuspended in an electrolyte which consists in passing said materials ina coherent liquid phase through a restricted passage under controlledconditions subjecting suc- 1 cessive portions of said material while insaid passage to an arc caused by electrical current of high densitythereby heating said successive portions of liquid and collecting,cooling and condensing the resultant material.

12. The process of heat treating materials containing a hydrocarbonmixed with an electrolyte containing catalytic materials, which consistsin passing successive portions of said materials, in coherent liquidphase, through a restricted passage under controlled conditions, formingan electric arc in said material by the direct flow of electric currentin said passage, and removing and collecting the resultant material.

WILLIAM A. DARRAH.

